On this day, March 15, in hip-hop history...

2015: Compton rapper Kendrick Lamar dropped his sophomore album, To Pimp a Butterfly, on March 15, 2015.

Coming off the momentous acclaim of his major label debut, good kid, m.A.A.d city in 2012, everyone in hip-hop had an ear out for what K-Dot would come up with next. Hailed as one of the most nimble, imaginative storytellers in the rap game today, Lamar's second album had high expectations. Originally set to drop on March 23, Top Dawg Entertainment, Aftermath and Interscope moved up the release, surprising fans with a late night drop one day after the 20th anniversary of 2Pac's Me Against The World.

The album's lead singles, "Blacker The Berry," "King Kunta" and "Alright" asserted an unapologetically Black message in the wake of the police brutality trend in America and the shooting deaths of young Black men like Michael Brown, Tamir Rice, Eric Garner and more while cuts like "Momma," "How Much A Dollar Cost" and "Institutionalized" examined Kendrick's personal struggle with newfound fame and guilt for leaving the hood that raised him. The record was almost immediately hailed as a classic among fellow MCs and music fans for its inventive use of funk influences, and Kendrick's outstanding lyricism. Production credits on TPAB include Dr. Dre, Anthony "Top Dawg" Tiffith, Terrace Martin, Flying Lotus and Pharrell Williams and though it was sparse with features, George Clinton, Snoop Dogg and Rapsody came through with memorable verses when they did assist. The album debuted at no. 1 on the Billboard 200 and broke a Spotify single day streaming record, being streamed 9.6 million times in one day.

Kendrick spoke on TPAB's message when he sat down for his XXL Winter 2015 cover story. “The past few years or so has been very politically charged and controversial. From Trayvon Martin, to Eric Garner to Michael Brown and issues of police brutality and racism and for so many other reasons. All of it has really struck a nerve with me because when you experience things like that personally and you know the type of hardships and pain that it brings first-hand, it builds a certain rage in you. It brings back memories of when I’m 16 and the police come kicking the door in. They don’t care that I’m a little boy and they stumped me in my back two times and they dragged me out the house and have us all handcuffed. It brings back those memories. Memories of losing loved ones. It brings back some of the most painful memories and deepest thoughts of real life situations that I didn’t even want to address on good kid. Or wasn’t ready to. Rage is the perfect word for it.”

As far as accolades, TPAB was the highest rated hip-hop album of the year, ending up on every major outlet's "Best of the Year" list. TPAB was nominated for 11 Grammy Awards, including Best Rap Album and Album of the Year. At the 2016 Grammy Awards, K-Dot won five of his eleven nominations including Best Rap Performance for "Alright" and Best Rap Album but lost Album of the Year to Taylor Swift's 1989.

Four years out from the release, the living legacy of TPAB serves as a reminder of the power of hip-hop.

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